And what about governor romney? What does he plan to do as the race enters the final stretch? Abc's jonathan karl tells us about that. Reporter: Mitt romney was back on the campaign trail again today in florida -- but with a twist. Gone was any criticism of the president, replaced with talk of unity. Look, we can't go on the road we are on. We can't change course in america if we keep on attacking each other. We have got to come together and get america on track again. Reporter: Recent polls in florida show the race here in a dead heat. Romney's most prominent florida supporter told us it is hard to imagine him getting elected if he doesn't win here. I think it's very important to win and obviously difficult to come up with a formula for victory, I am sure there is one, but let's not even try. Let's win florida. Reporter: Just as important for romney is ohio, where he is under fire for ads suggesting u.S. Automakers are about to ship jobs to china. Obama took gm and chrysler into bankruptcy and sold chrysler to italians who are going to build jeeps in china. Reporter: Chrysler and gm angrily denied that they are shifting u.S. Production to china. And joe biden accused romney of lying and causing panic among autoworkers in ohio. Thousands of them are calling their uaw reps, "is it true, is it true? Is jeep really going to leave? Is the announcement not true? Are they going to shut down our plant?" What a cynical, cynical thing to do. Reporter: But the romney campaign does see some positive signs out there, especially in pennsylvania, minnesota and michigan. Three states that have been considered solidly democratic, but where the obama campaign is now suddenly playing defense, spending more than $1 million on tv ads for the final week.

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